fix the doc-comment-decoration-trimming edge-case rustdoc ICE#47210

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bors merged 1 commit intorust-lang:masterfrom

zackmdavis:the_3rd_of_2_hardest_problems_in_computer_science

Jan 9, 2018

Commits on Jan 6, 2018

wherein careful doc-decoration arithmetic proves quite the ICE-breaker
zackmdavis
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